Search for: deposits
0.019 seconds
Total 657 records

    Analyses of Effect of Bank Branching on Deposit Market Share and Market Size in Iran Banking Industry

    , M.Sc. Thesis Sharif University of Technology Yousefi, Fateme (Author) ; Fatemi, Farshad (Supervisor)
    This thesis aim to the study of the effect of bank’s branching decisions on deposit market. Using panel data banks from Iran, we study effect of branching on market share and market size. In theoretical part, we assume that banks maximize discounted flow of the profits. We also assume that the banks take into account the reaction from rival banks in setting number of branches. Banks are assumed to expect the rival banks react by a lag of one period. In empirical part, in order to distinguish between aggregate market size effect and market share effect, we rewrite quantity of deposit in banks as the product of aggregate deposit and market share. We specify deposit market share function with... 

    Computational Simulation of the Effect of Breathing Particle Mass and Breathing Frequency on a Human Respiratory System

    , M.Sc. Thesis Sharif University of Technology Goodarzi Ardakani, Vahid (Author) ; Tayyebi Rahni, Mohammad (Supervisor)
    Our surrounding environment is full of particles with different sizes. These suspended particles enter our body through respiration process, which of course has some negative effects. Therefore, it is very important to comprehend the mechanisms and the effective parameters on these particles motion and their deposition inside the human airway. This work numerically investigates the effects of particles mass and breathing frequency on the deposition of particles in human respiratory system. To this end, a realistic 3-D model of human respiratory system geometry, including nostrils, vestibule, nasal cavity, human sinuses, nasopharynx, oropharynx, larynx, trachea, and main bronchus has been... 

    Control of Elements Ratio in Alloy Deposition System

    , M.Sc. Thesis Sharif University of Technology Kishani Farahani, Esmat (Author) ; Rashidian, Bijan (Supervisor)
    Nowadays, thin film alloy deposition has much importance. These alloys are used for various opto-electronic device applications such as liquid crystal displays, flat panel displays, plasma displays, solar cells and computer memories. Exact control of elements ratio in alloy is one of the important issues in deposition of thin film alloys. In alloy deposition with electron beam gun method from its elements, uniformity improvement of each layer is a way to maintain elements ratio in different parts of sample. This uniformity has much importance especially in optical coatings such as high quality antireflection coatings, highly selective filters and low loss reflectance coatings. In this... 

    Synthesis of Graphene Structures by Chemical Vapor Deposition Method and Evaluation of their Electrical and Biological Properties

    , M.Sc. Thesis Sharif University of Technology Kiani Shahvandi, Fatemeh (Author) ; Simchi, Abdolreza (Supervisor)
    Graphene is a newly developed nanomaterial that has resived considerable attention in recent years. Graphene – based structures having remarkable properties, e.g. high specific surface area, ultrahigh electrical conductivity and good biocompability, are ideal choices for nanomedical applications such as biosensors and cell culture scaffolds. So, in this project 2D graphene and 3D graphene foam structures were synthesized by chemical vapor deposition (CVD) method and their electrical and biological properties were evaluated. First step of this project was to design and make a CVD system suitable for the synthesis of high quality graphene structures, i.e. single layer graphene and 3D graphene... 

    Synthesis of Titanium Nanoparticles from Titanium Tetrachloride and Potassium Vapors Via Chemical Vapor Condensation Process

    , M.Sc. Thesis Sharif University of Technology Kookhaee, Hamed (Author) ; Halali, Mohammad (Supervisor)
    Titanium nanoparticles were synthesized by chemical vapor condensation (CVC) process. Titanium tetrachloride (TiCl4) as titanium’s precursor reacted with potassium as reductant, in vapor phase and the products were titanium nanoparticles encapsulated in potassium chloride. Dried Argon gas was employed as carrier gas. Resulting powders gathered in ethanol bath. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and atomic adsorption spectroscopy (AAS) analysis were used to characterizing the products. The effect of Argon gas flow on nanoparticles size was investigated in this research. The particle size decreases with increasing Argon gas flow. The size of nanoparticles was under... 

    Modification of Vertically Aligned Carbon Nanotubes with RuO2 for a Solid-State pH Sensor

    , M.Sc. Thesis Sharif University of Technology Kahram, Mohaddeseh (Author) ; Dolati, Abolghasem (Supervisor)
    In this work, a novel type electrode based on RuO2 nanoparticles-modified vertically aligned carbon nanotubes (RuO2/MWCNTs) was investigated. ThisRuO2/MWCNTs electrode not only shows a high capacity nature,but also possesses a good response to the pH value. In order to develope this sensor, aligned carbon nanotubes were synthesized by the chemical vapor deposition at first and then modified with RuO2 nanopartcles by sol-gel method. Various parameters affecting the growth of nanotubes, such as substrate type, surface finishing, surface roughness, the growth temperature and carbon feed rate was studiedand and optimal conditions for growth were obtained. At last, aligned nanotubes with a... 

    Investigation on Electrical Properties and Band Structure of Barium Strontium Titanate Thin Films Grown by Pulsed Laser Deposition

    , M.Sc. Thesis Sharif University of Technology Kashir, Alireza (Author) ; Nemati, Ali (Supervisor) ; Mahdavi, Mohammad (Co-Advisor)
    In this research the microstructural, electrical and optical properties of Strontium Titanate and Barium Strontium Titante thin films, fabricated through Pulsed Laser Deposition (PLD), were investigated. X-ray Photoelectron Spectroscopy and X-ray Diffraction study showed that the stoichiometry of the target material was highly preserved by using PLD method. Scanning Electon Microscopy as well as Atomic Force Microscopy depicted that the using of pressed and sintered target is a suitable metod for improving the surface quality of the thin films. Using the pressed target decreased the quality of the thin films and the average roughness of the films increased. The main reason for this... 

    Experimental and Modeling Investigation of the Near Wellbore Asphaltene Deposition Damage Removal by Ultrasonic Waves

    , M.Sc. Thesis Sharif University of Technology Keshavarzi, Behnam (Author) ; Ghotbi, Cyrus (Supervisor) ; Ghazanfari, Mohammad Hossein (Co-Advisor)
    This work concerns with experimental and modeling investigation of the asphaltene damage removal using ultrasonic wave irradiation. A specific core holder apparatus was designed and utilized for in situ ultrasonic exposure to damaged core plug at different conditions of exposure time, ultrasound power and distances between sound source and plug. Injection of many pore volumes of an asphaltenic crude oil was used for creating asphaltene induced damaged in porous media through permeability measurements. The deposited asphaltene during oil injection as well as asphaltene removal due to ultrasonic exposure was evaluated using IP-143 analysis. The results revealed that ultrasound application... 

    Characterization of Urban Stormwater-borne Solids in Tehran Metropolitan City, Iran

    , M.Sc. Thesis Sharif University of Technology Kazemi Parkouhi, Fatemeh (Author) ; Tajrishy, Massoud (Supervisor)
    Stormwater-borne solids are a major contributor to water quality degradation. A large portion of water quality impaired surface waters is located in urban areas and stormwater runoff is a major source of contamination. Sediments have been identified as the most widespread pollutant in urban river and streams. Water quality of urban streams in Tehran was characterized by determining the PSD, total phosphorus (TP), orthophosphate, NO3, NO2, NH3, TSS, TDS, heavy metals and turbidity in six storm events and base flow. A total of 45 road-deposited sediment (RDS) samples were collected from three different land-use types (residential, intense traffic and educational) in Tehran for characterization... 

    Modeling and Improving the Thickness Distribution in Vacuum Coating System

    , M.Sc. Thesis Sharif University of Technology Chaghazardi, Zahra (Author) ; Rashidian, Bizhan (Supervisor)
    In the fabrication of semiconductor devices, uniformity of thin films has many important influences on optical and electrical properties of the device. many attempts have been done on the enhancement of the uniformity of thin films so far. In this thesis, first the effect of angular variation of source with respect to the target on uniformity in the evaporation coating system has been studied, then an in situ positioning system for substrate has been designed and fabricated. After finding the thickness’s profile for Ag and Cu in Electron Beam Gun system, we studied the motion pattern of the target for improving the uniformity. This positioning system can be used to any coating systems. in... 

    Corrosion Resistance of Graphene-Titania Coating on 316 Stainless Steel by Electrophoretic Deposition

    , M.Sc. Thesis Sharif University of Technology Parvizi, Sahar (Author) ; Afshar, Abdollah (Supervisor)
    The aim of this thesis was creating Titania/RGO coating with electrophoretic method to evaluate the corrosion resistance of stainless steel 316. At first Graphene Oxide were synthesized with modified Hammers method and their physical, chemical and morphological properties have been investigated using XRD, FTIR, EDX, TGA, UV-Vis and Raman analysis. then Graphene Oxide was added to the bath of titanium and was deposited on 316 stainless steel substrates. Moreover, corrosion protection of coating has been examined using Poarization test and Electrochemical Impedance Spectrometry. The effect of deposition parameters on corrosion properties of composite coatings were examined. The key variables... 

    Wear-Resistant Nickel-Titanium Nitride Composite Coating by Electrochemical Method

    , M.Sc. Thesis Sharif University of Technology Parhizkar, Nafise (Author) ; Dolati, Abolghasem (Supervisor)
    Metal matrix nanocomposites contains ceramic ultrafine particles in a metal matrix, are used to improve the mechanical properties such as hardness and wear of coatings. For developing metal matrix nanocomposites, there are many methods. Electrochemical deposition process is one of these methods that have some advantages like uniform depositions on substrates with complex shapes, low cost, good repeatability and reducing waste. In this project, for increasing the hardness and wear resistance of nickel, composite coatings of nickel - titanium nitride was created by using electrochemical deposition of Watts bath contained titanium nitride particles. In order to increase the amount of... 

    The Effect of Surface, Morphology, and Composition of Semiconductor Layer on the Back Reaction of Electrons in Dye Sensithized Solar Cells:Theoritical and Experimental Investigation

    , Ph.D. Dissertation Sharif University of Technology Pazoki, Meysam (Author) ; Taghavinia, Nima (Supervisor) ; Nafari, Nasser (Supervisor)
    This thesis deals with a theoretical and experimental investigation of different approaches for reduction of electronic recombination in the semiconductor/Dye interface of dye sensitized solar cells (DSSC) including dye coverage, core-shell structures and energy level distributions. Interface of ZnO/TiO2 in the core-shell structure have been studied by density functional theory and the energy level distribution of surface atoms, recombination and Fermi level changes, open circuit voltage and surface dipole distributions have been discussed.
    The presence of TiO2 shell increases the ZnO surface dipole moment, and shifts the ZnO conduction and valence bands to higher energies. Also, it... 

    Electrodeposition of Platinum Nanowires

    , M.Sc. Thesis Sharif University of Technology Hashemi Darian, Sahar (Author) ; Dolati, Abolghasem (Supervisor) ; Ghorbani, Mohammad (Supervisor)
    Platinum nanowires were prepared by electrodeposition in polycarbonate membrane, with different average diameter of nanowires about 15, 50 and 100 nm and the height about 6 µm. Kinetics of electrodeposition process were studied by electrochemical techniques such as voltammetry and chronoamperometry methods. Diffusion coefficient was then calculated from the electrochemical parameters and consequently the density of primer nuclei was extracted. The morphology of Pt nanowires was characterized by SEM, TEM and EDX. The results show that growing Nanowires on the surface of template is branch-like. The electro-oxidation of methanol and hydrogen on this electrode is investigated at room... 

    Kinetic Modeling of Coke Formation and Deactivation in Catalytic Dehydrogenation of Propane

    , M.Sc. Thesis Sharif University of Technology Niknaddaf, Saeid (Author) ; Khorasheh, Farhad (Supervisor) ; Nazeran, Iraj (Co-Advisor)
    The study on the propane dehydrogenation process has been receiving significant attention due to the growing demand for propylene. Many efforts have been made to enhance the propylene yield by developing new catalysts with high-activity, high-stability and high-selectivity. Among these, platinum supported catalysts have been reported widely. Firstly, the current study mentions related work in the modeling of coke formation and deactivation of catalyst, experimental setup and catalysts which are conventionally used for propane dehydrogenation reaction. Then, a monolayer–multilayer mechanism is proposed for modelling the coke formation. In addition, the reaction rate of coke formation and its... 

    Modeling of Nano-Aerosol Deposition in Human Lung in Successive Respiratory Cycles

    , M.Sc. Thesis Sharif University of Technology Nemati, Hossein (Author) ; Saeedi, Mohammad Saeed (Supervisor) ; Hosseini, Vahid (Co-Advisor)
    Particulates are a group of air pollutants. They can enter the respiratory system by breathing and cause adverse effects on its performance. Also, inhaled drugs, recently have found many applications in the field of drug delivery. Prediction of particle deposition in the lungs during breathing, can provide useful information on the effects of deposited particles on the respiratory system. When a person is exposed to breathable particulates, after a while with completion of a few respiratory cycles, particle deposition rate, reaches a certain amount at the quasi-steady state. A lot of researchers have investigated particle deposition in the lung, but all of them have studied a single... 

    The Effect of Metal Oxides on Gasochromic Properties of WO3 Thin Films Formed by Pulsed Laser Deposition

    , M.Sc. Thesis Sharif University of Technology Nematollahi, Mohammad Reza (Author) ; Mahdavi, Mohammad (Supervisor)
    Physical and chemical properties of tungsten oxide thin films change reversibly while exposure to hydrogen gas. This property is called gasochromic. To enhance optical properties of such films, nanostructured, amorphous and porous thin films of (WO3)1-x(MeO)x (MeO= TiO2, MoO3, NiO; x=0.09, 0.17, 0.23, 0.29, 0.33) were fabricated by Pulsed Laser Deposition. Molar percentage of Me/W (Me= Ti, Mo and Ni) was changed in films with respect to targets; for Ti and Ni always a reduction, but for Mo an enhancement for low percentages was observed. The reason is the existence of thermal ablation mechanism during deposition, in the other word is different vapor pressure effect. An increment in x for... 

    Design and Prototyping of a Continuous Coaxial Nozzle for Uniforml Metal Powder Deposition at Various Angles

    , Ph.D. Dissertation Sharif University of Technology Nasiri Khansari, Mohammad Taghi (Author) ; Movahhedy, Mohammad Reza (Supervisor)
    Direct metal deposition (DMD) process is an additive manufacturing technology that is rapidly gaining laser importance due to its various capabilities in applications such as coating, repairing high-value damaged parts, rapid prototyping and even production in small quantities. Among the equipment needed for this process, nozzle is perhaps the most important component because its performance affect the efficiency of powders trapped in the molten pool, and is crucial to the quality of the deposited layer. The existing nozzle designs can be categorized in two groups; lateral and coaxial nozzles; and the coaxial ones are divided into continuous and discontinuous types. Coaxial nozzles have... 

    Liquid-liquid-Solid Three Phase Flow in Horizontal Well on Bottom Hole Condition

    , M.Sc. Thesis Sharif University of Technology Nejati Ali Gorzani, Hamed (Author) ; Shad, Saeed (Supervisor)
    When producing oil reservoirs, if the reservoir formation has a low resistance, the entry of sand into the oil wells is definite. Creating a bed of sand particles at the bottom of the tube can cause operational problems such as reduced production and excessive drop in pressure, equipment failure, erosion and corrosion. By keeping the velocity above the sedimentation rate (the speed of solid particles always moving and above the bottom of the tube), preventing these problems can be prevented. A wide analysis of the flow regime in the horizontal and sloping pipelines for the flow of water, oil, and sand has been made in this context. Also, the effect of sand concentration on the flow regime... 

    Multiphysics Modeling and Magnetic Control of Powder Deposition Process in DMD Method of Additive Manufacturing Technology

    , M.Sc. Thesis Sharif University of Technology Nejati Eghteda, Sina (Author) ; Movahhedy, Mohammad Reza (Supervisor)
    Direct Metal Deposition is one of the methods of Additive manufacturing that has seen the most spread in recent years. In this method metal powder is directed towards the free surface of the workpiece through a nuzzle, and is simultaneously heated to become molten in a melting pool by a laser beam and begins the deposition process. One of the parts that make up a DMD system is powder feeding nuzzle. These nuzzles usually encounter a similar fundamental problem: that the effect of gravity on the stream of metal powder and the carrier fluid causes this stream to deviate from its intended position. To prevent this, nuzzles are usually designed with a fixed downward angle and the angle of the...